Intraosseous devices for causing at least a portion of a needle assembly (which comprises a cannula) to penetrate into a bone are well known in the art. Such devices are typically used in life saving cases where the injection of drugs to the blood circuitry is required, while it is difficult for the medical staff to locate the patient's vein within a reasonable time. This device is also used for the extraction of a sample from a patient's bone marrow.
There are several specific locations at the patient's body where this procedure can be performed, such as the proximal Tibia, Distal Tibia, Humeral Head, and Distal Radius. One preferred location at the patient's body where this procedure is typically performed is the sternum, which is located at the upper chest. More specifically, the insertion is typically performed on the Manubrium, which is the upper part on the Sternum.
However, there are several problems that are associated with an intraosseous procedure which is performed at the sternum (but may exist also at other bone locations), or that are associated with prior art devices, as follows:                a. The sternum has a relatively small surface, while it is very important to perform the procedure exactly at the sternum center. Therefore, additional means have to be provided in order to exactly determine the penetration location prior to performance of the procedure;        b. The sternum is fragile, and may break if the penetration is not performed exactly at the sternum center, or if it is performed with an excessive force. If the procedure results in breakage of the sternum, the procedure fails causing an additional damage to the patient and a serious threat for his life;        c. From the above described problems it becomes clear that an intraosseous device has to introduce the cannula very accurately at the sternum center. Moreover, the penetration depth to the sternum (i.e., beyond the sternum front surface) has to be made very accurately (typically to a depth of 6 mm) in order for the procedure to succeed. However, unfortunately it has been found that typical automatic intraosseous devices at which the penetration depth is predefined cannot efficiently operate at the sternum. This is particularly due to the fact that in those prior art devices the user typically adjusts the total penetration depth, which is a sum of the thickness of the tissue above the bone and the of the penetration depth of the cannula to the bone (herein, the term “tissue above the bone” refers to the tissue which is located between the bone, such as the sternum, and the patient's skin). However, such a total penetration depth definition cannot reliably operate at the sternum, as it is known in the art that the thickness of tissue above the sternum very significantly vary from one person to another, leaving the actual penetration depth to sternum to be very inaccurate. Although several of prior art devices overcome this problem, still these devices suffer from other problems, i.e., of being non-automatic devices, from being unsafe or inaccurate with respect to the penetration location, etc.;        d. Still another problem relates to the safety of operation issue. Typically, prior art devices are provided some safety means (such as a safety catch) for preventing erroneous operation. However, none of said safety means is connected to the appropriate location of the penetration, once this location has been determined. More specifically, other prior art devices may be operated on other locations of the human body once their safety means have been released. It is desired to provide a device which becomes operable (by the release of one of its safety means) only at the correct location, once this location has been determined;        e. Several prior art device for the injection to the sternum still suffer from the drawback they are not automatic, requiring the user to perform a relatively complicated manipulation. It is desired to provide a fully automatic device, which still resolves all the above problems.        
U.S. Pat. No. 633,199, U.S. Pat. No. 5,817,052, US 2010/0298830, US 2010/0160868, US 2003/0225344, US 2010/0298831, US 2008/0208136, US 2006/0015066, US 2010/0160867, US 2010/0152616, US 2010/0137740, US 2006/0052790, US 2005/0171504, US 2003/0225411, and US 2010/0312246, all describe some sorts of intraosseous devices, at least some of them describe means for the introduction of as cannula into the sternum.
FASTx™ Literature Review and Bibliography (publication date is unknown), http://www.pyng.com, provides some background and a structure of device for the introduction of a cannula into the sternum.
It is therefore an object of the present invention to provide an automatic intraosseous device that can introduce a cannula to a specific depth of a bone, irrespective of the thickness of the tissue above the bone.
It is another embodiment of the invention to provide a kit which comprises, in additional to the automatic intraosseous device, means for accurately determining the right location for penetration, particularly when this location is the sternum.
It is still another object of the present invention to provide safety means at said device that releases the device from a locked position, only when the device is positioned at the right location for penetration, once this location has been determined, while preventing any operation at other locations.
It is still an object of the present invention to provide all said features and advantages in a device which is fully automatic.
Other objects and advantages of the invention will become apparent as the description proceeds.